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Akka :: Using Messages with Different Priorities in the Flow of Events in ActorSystem

I need to publish messages of different types to the event stream, and those messages must have different priorities, for example, if 10 messages of type A were published, and one message of type B was finally published, and priority B is higher than priority A - message B should be selected the next player, even if there are 10 messages in type A.

I read about priority messages here and created my simple implementation of this mailbox:

  class PrioritizedMailbox(settings: Settings, cfg: Config) extends UnboundedPriorityMailbox(

    PriorityGenerator {
      case ServerPermanentlyDead => println("Priority:0"); 0
      case ServerDead => println("Priority:1"); 1
      case _ => println("Default priority"); 10
    }

  )

then I configured it in application.conf

akka {

    actor {

        prio-dispatcher {
            type = "Dispatcher"
            mailbox-type = "mailbox.PrioritizedMailbox"
        }

    }

}

and connected to my actor:

private val myActor = actors.actorOf(
  Props[MyEventHandler[T]].
    withRouter(RoundRobinRouter(HIVE)).
    withDispatcher("akka.actor.prio-dispatcher").
    withCreator(
    new Creator[Actor] {
      def create() = new MyEventHandler(storage)
    }), name = "eventHandler")

I use ActorSystem.eventStream.publish to send messages, and my actor (I can see in the logs that the messages are being processed, but in FIFO).

, , logs/console "Default priority". - ? ? eventStream?

+5
1

, , , , , . :

  trait Foo 
  case object X extends Foo 
  case object Y extends Foo 
  case object Z extends Foo 

  class PrioritizedMailbox(settings: ActorSystem.Settings, cfg: Config) 
extends UnboundedPriorityMailbox( 
    PriorityGenerator { 
      case X ⇒ 0 
      case Y ⇒ 1 
      case Z ⇒ 2 
      case _ ⇒ 10 
    }) 

val s = ActorSystem("prio", com.typesafe.config.ConfigFactory.parseString( 
        """ prio-dispatcher { 
        type = "Dispatcher" 
          mailbox-type = "%s" 
        }""".format(classOf[PrioritizedMailbox].getName))) 
      val latch = new java.util.concurrent.CountDownLatch(1) 
      val a = s.actorOf(Props(new akka.actor.Actor { 
        latch.await // Just wait here so that the messages are queued up 
inside the mailbox 
        def receive = { 
          case any ⇒ /*println("Processing: " + any);*/ sender ! any 
        } 
      }).withDispatcher("prio-dispatcher")) 
      implicit val sender = testActor 
      a ! "pig" 
      a ! Y 
      a ! Z 
      a ! Y 
      a ! X 
      a ! Z 
      a ! X 
      a ! "dog" 

      latch.countDown() 

      Seq(X, X, Y, Y, Z, Z, "pig", "dog") foreach { x => expectMsg(x) } 
      s.shutdown()

+10

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